SYNTHESES AND CRYSTAL-STRUCTURES OF THE POLYTELLURIDO COMPLEXES (PPH4)4[M2TE12] OF COPPER(I) AND SILVER(I)

The title compounds have been prepared as black crystal needles by reactions of Na2Te3 with CuCl and AgNO3, respectively, in dimethylformamide in the presence of PPh4Br. With regard to the large cell dimensions the crystal structure determinations were done by an imaging plate instrument. (PPh4)4[Cu2Te12]: Space group P2(1)/n, Z = 6, 51338 detected reflections, structure determination with 14 177 unique reflections with I > 4sigma(I), R = 0.081. Lattice dimensions at - 50-degrees-C: a = 1 704.5, b = 1 694.5, c = 5 044 pm, beta = 94.20-degrees. (PPh4)4[Ag2Te12]: Space group P2(1)/n, Z = 6, 80811 detected reflections, structure determination with 16092 unique reflections with I > 3sigma(I), R = 0.052. Lattice dimensions at - 50-degrees-C: a = 1 703.8, b = 1 722.9, c = 5 123 pm, beta = 94.65-degrees. The structures of the isotypic compounds consist of six symmetry independent PPh4+ ions and two symmetry independent anions [M2Te12]4-, in which the metal atoms of two (MTe4)--fivering fragments are linked by a Te4(2-) chain.